2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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9 * notice, this list of conditions and the following disclaimer.
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11 * notice, this list of conditions and the following disclaimer in the
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13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
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33 * @(#)ring.h 8.1 (Berkeley) 6/6/93
40 #if defined(__STDC__) || defined(LINT_ARGS)
47 * This defines a structure for a ring buffer.
49 * The circular buffer has two parts:
51 * full: [consume, supply)
52 * empty: [supply, consume)
57 unsigned char *consume, /* where data comes out of */
58 *supply, /* where data comes in to */
59 *bottom, /* lowest address in buffer */
60 *top, /* highest address+1 in buffer */
61 *mark; /* marker (user defined) */
63 unsigned char *clearto; /* Data to this point is clear text */
64 unsigned char *encryyptedto; /* Data is encrypted to here */
65 #endif /* ENCRYPTION */
66 int size; /* size in bytes of buffer */
67 u_long consumetime, /* help us keep straight full, empty, etc. */
71 /* Here are some functions and macros to deal with the ring buffer */
73 /* Initialization routine */
75 ring_init P((Ring *ring, unsigned char *buffer, int count));
77 /* Data movement routines */
79 ring_supply_data P((Ring *ring, unsigned char *buffer, int count));
82 ring_consume_data P((Ring *ring, unsigned char *buffer, int count));
85 /* Buffer state transition routines */
87 ring_supplied P((Ring *ring, int count)),
88 ring_consumed P((Ring *ring, int count));
90 /* Buffer state query routines */
92 ring_empty_count P((Ring *ring)),
93 ring_empty_consecutive P((Ring *ring)),
94 ring_full_count P((Ring *ring)),
95 ring_full_consecutive P((Ring *ring));
99 ring_encrypt P((Ring *ring, void (*func)())),
100 ring_clearto P((Ring *ring));
101 #endif /* ENCRYPTION */